27 July 2019 | New Scientist | 27for, as their kinetic energy is
equivalent to half a kiloton of
TNT explosive. Routinely, Earth
is hit by bolides with energy
equivalent to tens or hundreds of
kilotons of TNT, and nobody but a
few astronomers and the Nuclear
Test Ban Treaty monitors notices.
The Breakthrough Starshot
project talks of zipping past Alpha
Centauri. A quick way to the
nearby Proxima Centauri and its
putative planet has been proposed
by astrophysicists René Heller
and Michael Hippke. It involves
braking at Alpha Centauri and
performing a gravitational
slingshot, before drifting to
Proxima Centauri at a relatively
sedate pace. This braking could be
achieved by sending probes with
light sails large enough that they
can be “flipped” and so decelerate
using the light of Alpha Centauri.
Successful surgery isn’t
just about surgeons
15 June, p 20
From Andrew Vickers,
Lancaster, UK
Ruby Prosser Scully highlights
the growth of robotic surgery
and questions whether it achieves
better outcomes. Many factors
may contribute to this growth,
including profit from offering
“space-age treatment” and the
temptation of toys for the boys.
But assessing the outcome
of surgery based solely on the
skill of the surgeon hasn’t been
appropriate since 1847, when
anaesthesia was introduced. Now
surgery is a team effort, including
pre-operative optimisation,
management by an anaesthetist
and others during surgery and
post-operative care. All these
factors need to be considered
when assessing putative benefits
of robot-assisted surgery.
In extremis, I would be happy
to accept a skilled surgeon
operating at a distance via a robot,
with supporting staff who are
unfamiliar with the procedure. For
planned surgery, however, I want
to be managed by a team working
in a centre where the procedure in
question is carried out regularly
and successfully.Our brains may depend on
a discovery of cooked food
22 June, p 34
From Neil Doherty,
Wilthorpe, South Yorkshire, UK
Sam Wong writes that our
intelligence was possibly enabled
by the invention of cooking. But
to say that we invented cooking is
to suggest that someone once sat
down and thought: “I could set
some stones up in a ring... then
rub a couple of sticks together” –
and simultaneously invented
fire and cooking.
Injured or slow-moving animals
caught in fires caused by volcanoes
or lightning provided plenty of
opportunities to discover cooked
meat. Tens of thousands of years
later, perhaps our brains had wired
up sufficiently to invent a place
suitable for us to cook in.What should get in a flap
over this tiny flying robot?
6 July, p 16
From Steve Dalton,
Chipstead, Kent, UK
The RoboBee X-wing is an amazing
piece of engineering. But is it bird
and bat-proof? More importantly,
are birds and bats it-proof?For the record
❚ The primary motor cortex is
nearer the front of the brain than
we showed it (22 June, p 34).
❚ Still floating in a tin can: the
Apollo 11 mission took 75 hours
49 minutes to get from Earth to
lunar orbit (13 July, p 37).25 years ago, New Scientist
was viewing an eagerly anticipated
astronomical catastropheIT WAS, we wrote on 23 July
1994, the astronomical event
of the century: the first time we
had ever had advanced notice
of a collision between a comet
and a planet. And it lived up to
its billing. “Only the most naive
amateur astronomers could
have been disappointed by the
fireworks when the fragments
of Comet Shoemaker-Levy 9 hit Jupiter this week,”
wrote our correspondent Jeff Hecht.
The comet had been discovered by astronomers
Carolyn and Eugene Shoemaker and David Levy
the year before, orbiting Jupiter on a wildly eccentric
course – one that would lead to its spectacular end
in the upper atmosphere of the gas giant.
Better still, from a planetary science point of view,
there would be more than one collision to observe.
When the comet was spotted, it had already been
broken up into pieces by Jupiter’s gravity, thought to
have happened in 1992, with the rocks strung out
in a line like pearls.
“The fragments hit the far side of Jupiter, so the
collisions could not be observed directly from Earth,”
we advised anyone worried they might have missed
something. “However, they were close to the visible
edge of the planet,” Hecht wrote, “and Jupiter’s rapid
rotation – its day is only 10 hours long – brought the
crash sites into view a few minutes after the fragments
hit the Jovian atmosphere.”
Fragment A entered Jupiter’s southern hemisphere on
16 July 1994. Over the next six days, 21 impacts were
seen. The largest was on 18 July, when fragment G hit,
creating a dark spot over 12,000 kilometres across.
The following week, on 30 July, Hecht catalogued
an exhausting week of feverish observation. “During
the week-long spectacle, telescopes around the world
recorded thousands of pictures at every possible
wavelength – visible, infrared and ultraviolet,” he
wrote. “The cataclysmic images included fireballs
2000 kilometres across rising above the rim of Jupiter.”
The images were enough to frighten the US Congress
into taking the possibility of asteroids and comets
heading towards Earth a bit more seriously. “As pieces
of comet pelted Jupiter last week,” Hecht reported, “the
House Committee on Science, Space, and Technology
decided that NASA should be required ‘to catalogue and
track any major comets or asteroids that may cross the
orbit of the Earth’.” Simon IngsTo find more from the archives, visit
newscientist.com/old-scientistViews From the archives
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